Monoazo compounds



Patented Nov. 8, 1938 2,135,965 v MONOAZO COMPOUNDS a M iles' A. Dahlen,Wilmington, and Frithjof Zwilgmeyer, Arden, DeL, assignors to E. I. duPont deNemours & Company, Wilmington, Del., a

corporation of Delaware No Drawing. Application July 22, 1936,

,Serial No. 91,907 I 4 Claims. (01. 2605-197) 's PATE T; OFFICE Thisinvention relates to azo dyes, especially to new coupling components orintermediates which; may be used in the preparation of colors,particularly the so-called Diagens.

The azo dyes are a well-defined group containing the chromophor +N=N-.The chromogenof azodyestufis comprises two aryl radicalswithithechromophor between them. The mono azo-dyes are-generallyprepared by joining two componentsof which the first,an amine, is calledthe azorcomponent, and the second, usually a phenol, an'amine, or anactive methylene compound, is called the coupling component. In couplingthe components, the azo component isdiazotized-in amannerwhich will beunderstood bypersonsskilled in-theart, and'is reacted with the secondcomponent, often1in solution. Generally speakingnthearyl nuclei of the,azo dyes may contain certain substituents which change, but do notoriginate, the color of the dyestufis and are called auxochromes. Theauxochromes form a recognized'class, divided into two groups, of whichthe one'tends to make the dyestufi water-soluble, and the other doesnot. In this invention those auxochrome groups which tend tomake"the*dyestu'fiwater soluble are called s-auxochromes and those:which do not are called n-auxochromes. p

Thefpriorart azo dyes are applied to fabrics, orto' other materials tobe dyed, in three general ways: (11.) The dyestufl. is dissolved ordispersed a suitable'bath and thematerial is dipped in theibath'. To beusedinthi's manner'the completed' dyestuff must be substantiveto:thematerial which is to be dyed. (b) A substantive coupling componentis directly -ailixed to the fabric, which, is then. treated with thediazotlzed component, completing the dye on the material.

closed have been known.

1.,It isan object of the invention to provide new compoundswhich beuseful as;- coupling components for the preparation ofazo dyes. An otherobject, of the invention is to provid inter ponents orintermediatesofthe kind herein dis-w I I Y Y in which aryl representsthe nucleus of a primary'arylamine, oneX'represents an acyl aminof groupand the other X represents hydrogen; one Y represents 'OH and the otherY's represent; hydrogen. In; this intermediate the amino acyl" group maybe-"at'tached in the positions indicated in one benzene ring of thenaphthol nucleus and the hydroxyl may be attached in any position in theother'benzene ring of the naphthol. Aryl may be without substituents, orit may carry any auxochrome substituent in any or all of the possiblepositions.

In forming the coupling component the arylazo-amino-naphthol is formedfirst and then the amino group oi the naphthol is acylated. Thus, anarylamine of the general formula aryl-NH: withor without auxochromesubstituents is diazotized. This may be coupled under acid conditions toan amino naphthol compound in which the *NHz is substituted on one ofthebenzene rings of the naphthalene nucleus and. the; JQH is substitutedon the other. The aryla'zo amino-naphthol is finally acylated to producethe aryl-azoeacylamino-naphthol which is the "coupling componenthaving'generally the structure'of the amine compound heretoforedescribed, the diflerence being that the coupling component has the'--NH acyl group instead of the 'NI-Iz group in the naphthol nucleus.Thus, this coupling component is represented by the general formula IIIHacyl in which the NH acyl is a substituent in one of the benzene ringsof the naphthol nucleus and the hydroxyl is a substituent of the otherbenzene ring of the nucleus.

These compounds may advantageously include auxochromes as substituentsin the aryl nuclei. The n-auxochromes' are, specifically thegroupsalkyl, alkoxy, halogen, arylo-xy; aralkyl, aralkoxy, aryl, hydroaryloxy,and trifiuoro-alkyl. Generalobtained by the substitution in thearyl-nuclei from one to three of these substituents'but more canbeused.j-.ZI.-'

The following examples are set forth asillustrative but not aslimitative of the invention.

Example I I I 13.8 parts of meta-nitraniline were diazotized in theusual manner and the diazo-salt coupled under acid conditions with 17.5parts of -1'-amino- 'l-naphthol. The precipitated product wasneutralized with caustic soda, filtered, washed and dried.

30 parts of the aryl azo naphthol amine havingthe aryl group of metanitraniline and the naphthol group of l-amino-7- -naphthol correspondingto the above described type aryl azo amine were produced. I I

About 30 parts of the amine wereacylated by heating with 40 parts ofacetic anhydride at 120 C. for 10 minutes. The reaction mass was drownedin ice and water and the precipitated product filtered off and washedfree-of acid. The precipitate was brought into solution with 60 parts ofalcohol and 120 parts of caustic soda of 30% strength at 70 C. Thesolution was cooled with ice to about 20 C., diluted with cold water toabout 600 parts total volume, and filtered to remove insoluble matter.The filtrate" was acidified with hydrochloric acid, and thereprecipitated material filtered, washed free of'acid and dried;

30 parts of the new coupling component of the following structure wereobtained;

The product is a yellowishebrown powder.

Example II purified as described in that example. 20.2 parts of thecoupling component of the following formula were obtained:

NHCOCH:

a on

The product is a dark brown powder.

ly speaking, entirely satisfactory results can be Example III the abovedescribed type amine were produced.

" About 30 parts of this amine were acylated with 30parts of aceticanhydride by a process similar to that described in Example I. 31.5parts of a brown coupling component of the following formula wereobtained:

. i H The product is a yellowish-brown powder.

Example IV I 13.8 parts of meta-nitraniline were diazotized in the usualmanner and coupled under acid conditions to 17.5 parts ofl-amino-6-naphthol, by the procedure described in Example I; 30 parts ofthe aryl azo naphthol amine of the type hereinbefore indicated, havingthe aryl group of metanitraniline and the naphthol group of 1-amino-6-naphthol were produced. l

' About 30 parts of this amine were acylated with 30 parts of aceticanhydride by the procedure described in Example I. 29.4 parts of thedark brown amino-azo compound represented by the following formula wereobtained:

-C -N=N- --NHCO on.

, f a... The product is a yellowish-brown powder.

Example V IIIHCOCH:

The product is a yellowish-brown powder;

' Example VI 10 parts of the amino azo compound produced in accordancewith Example III were benzoylated by treatment with an excess of benzoylchloride in aqueous-alkaline suspension. 'lheexcess benz'oyl "chloridewas hydrolyzed, and the insoluble productremoved by filtration. It waspurified by the procedure describedin Example'I. '11.0

parts of a brown coupling component of the fol lowing formula wereobtained:

The product is a rellowish brown powder. 7,

Eiample VII The acylated product produced in accordance with Example Iwas reduced with sodium sulfhydrate to reduce the N02 substituent of theaniline group producing the new coupling component of the followingformula:

NHz

l OH

The product is a yellowish- -brown powder.

- Example VIII Coupling component described in Example V11, was acylatedin the usual manner, yielding a new coupling component of thefollowingstructure-z NHooom j The productis a dark brown powder.

NHCOCHa The following Table I'lists additional coupling componentsprepared by. processes similar to the foregoing examples.

icolumn entitled Coupled to.

The third column entitled Acylated with shows the acid with which thearyl azo amine is acylated to form the coupling compound shown in thelast column which is entitled Formula of product.

Table I Example 353332;? Coupled to- Acylated with Formula of product IXAniline l:7-amino- Acetic-anhy 3N=N- NHCOGH! naphtha]. dride.

NBC 0 CH:

X 3-nitro-4-amino- 2:6-amiuo- 'rl' CH N=N toluene. naphthol.

XI Ani1i11e.- lz7-amino 'd0 "N=N NHCOGH:

naphthol.

CH3 7 I 4 I XII 4-oh1oro-2-amino- -.do ;do N= NHCOCH:

toluene. v

x111 i-nmo-z-ammo--Q 1O. Q; .i ab -N=N- NHooom anisole. v

NO: OH

(I) OH:

XIV 4-chloro-2-aminodo .i ....-.d N=N- NHeoom 1 anisole.

ill)

ess

Table .IContinued Example 3 23323 Coupled t0 Acylated witl1- I" vproduct I.

C H2CH2 XXV 4-ch1oro- 2 -amino- 1:7 a min 0 Hexahydro-ben- INHO O C H- OH;

anisole. naphthol. zoyl-chloride.

. CH2--CH2 XXVI .do (lo Methyl-chloro- NH-C 0 0 CH3 carbonate.

l O H XXVII 3-nitro-4-aminodo Acetic anhy- CH3ON=N NHOOCHa toluene.dride, I

XXVIII. Meta-nitraniline 1:5-a m i n 0- do N=N -NH0 0 CH3 naphthol.

N 0 2 HO The above examples point out only a few members of a largeseries of new monoazo compounds suitable for use as coupling componentsin Diagens and Ice Colors which may be made in accordance with theinvention. Generally speaking, all the arylamines commonly used in theIce Color and Diagen art may be diazotized and coupled under acidconditions with the aminonaphthols to form the coupling components ofthis invention, provided that the amino group is substituted on onebenzene ring of the naphthalene nucleus and the hydroxyl group issubstituted on the other. The amino-aryl-azo compounds obtained by thiscoupling may be acylated with any of the usual acylating agents. Inaddition to acetylation, benzoylation, furoylation,hexa-hydro-benzoylation and carbo-methoxylation, mentioned in theexamples, other illustrations of acylations are mentioned which may beeffected by the use of agents such as:

Propionyl-chloride Iso-valeryl-chloride Para-nitro-benzoyl-chlorideOrtho-chloro-benzoyl-chloride Alpha-naphthoyl-chloride Anthraquinonebeta-carbonyl-chloride Benzoic-anhydride Butyl-chloro -carbonatePhosgene I Para-nitro-phenyl-carbamyl-chloride It will be understoodthat the conditions for diazotizing the arylamines will be varied inaccordance with the nature of the arylamines, in the manner well knownin the art of azo color preparation. Likewise, the conditions ofacidity, temperature, etc., for the coupling of these diazosalts withthe amino-naphthols may be varied in accordance with the compounds used.The conditions selected in each instance are desirably those which yielda maximum of coupling in the ring containing the amino group, and aminimum of coupling in the ring containing the hydroxyl group.

It will be evident to those skilled in the art that the presentinvention can be utilized in various ways, for example, to makecompositions for dyeing, such as non-acid pastes, powders and liquidscontaining an azo component stabilized against reaction with thecoupling component. In the operation of dyeing, these compositions maybe applied to the material to be dyed in any suitable manner, and thenacidified, whereupon the dye is formed and affixed to the material. Byacidifying such compositions, insoluble pigments may also be preparedapart from the material to be dyed, and the pigments may be used invarious forms and with many different materials. In the preparation ofpastes and other compositions a variety of stabilizing agents known tothe art can be used, such as those commonly used in the preparation ofdeveloped azo dyes.

As many difierent embodiments of the invention will be apparent to thoseskilled in the art without departure from the spirit and scope of thedescribed invention, it is to be understood that no limitations areintended in the annexed claims except such as are imposed by the priorart or are specifically recited.

We claim:

1. The azo compound represented by the formula 2. Theazo compoundrepresented by the formula Il lH acyl 1 I OH in which there is at leastone substituent in aryl selected from the group consisting of hydrogen,amino, nitro and the n-auxochromes.

3. The azo compound represented by the formula.

Aryl---N=N in which X represents an amino acyl substituent.

4. An azo compound represented by the formula,

IIQ'H acyl in which one Y is hydroxyl and the other two Y's arehydrogen.

MILES A. DAHLEN. FRITHJOF ZWILGMEYER.

